1. Field of the Invention
The present invention relates to an image recording apparatus for performing both an exposure process by the laser irradiation and a heat development process by the application of heat on a heat development/photosensitive material or a photosensitive/thermal recording material which was drawn out from a mounting tray, to obtain a recording material on which an image has been formed. More specifically, the present invention is related to an image recording apparatus in which a transport path length of a recording material is short to shorten process time.
2. Description of the Related Art
Recently, it is strongly demanded to reduce liquid wastes in the medical field in view of the environmental conservation and the saving space. Therefore, a technique of related to photosensitive/heat-developing photographic materials for medical diagnosis and photograph, which enables to effectively expose with a laser image setter or a laser imager and enables to form clear black-colored images having high resolution and sharpness. A heat development process system is provided by using the photosensitive/heat development photographic materials. Since the heat development process system does not use chemical liquid products, the environmental pollution is eliminated. Further, it is simple for customers.
The same is required in the field of the general image forming materials. For example, since fine drawing is required for medical images, high image qualities having good sharpness and granularity is necessary for the medical images. Furthermore, it tends to be preferred cold black-tone images in view of diagnostic aspects. Although ink jet type printers and various sorts of hard copy systems utilizing pigment and dye for electro-photograph at present, there is no printer which satisfy necessary requirements as medical image output systems.
In contrast to the above-described hard copy systems, recently, a attention is paid to an image recording apparatus using dry systems without wet type process which enables to solve a problem related to process of liquid waste.
FIG. 2 shows an arrangement of a conventional image recording apparatus with the dry system.
This conventional image recording apparatus 1 mounting trays 5 and 6, a laser exposing unit 11, a heat development unit 15, and a transporting mechanism 17. The image recording apparatus 1 records an image on a recording material 3. The mounting trays 5 and 6 store therein sheet-shaped recording materials 3 for recording thereon images, and are made of a heat (thermal) developing/photosensitive material having a photosensitive characteristic and a thermo-sensitive characteristic. The laser exposing unit 11 forms a latent image of an image on a recording material 3 by irradiating thereon a laser by a laser exposing unit 9. The heat development unit 15 performs a heat development process with respect to the exposure-processed recording material 3 by applying heat by a heating means 13. The transporting mechanism 17 transports the recording materials 3 drawn out from the mounting trays 5 and 6 via the laser exposing unit 11 to the heat development unit 15.
JP-A-2000-321748 is known as a prior art.
In the image forming apparatus 1, a supporting mechanism 21 for supporting the recording material 3 when the laser is irradiated in the laser exposing unit 11 has one pair of rollers 23 and 24. The paired rollers 23 and 24 sandwich the recording material 3 at two front/rear positions which are separated from each other along a transport direction of the recording material 3.
In this structure, an intermediate portion of the recording material 3 is not fixed, and thus, an wobble may easily occur due to vibrations applied to the conventional image recording apparatus 1. Accordingly, there is a risk that exposure precision is deteriorated by the vibrations.
As a consequence, the laser exposing unit 11 is generally disposed at a lower portion of the image recording apparatus 1, where is hardly influenced by the vibrations.
Also, the heat development unit 15 is disposed at the uppermost portion of the image recording apparatus 1 in order that exhausted gas and heat, which are produced when heating process operation is performed, can be hardly close within this image forming apparatus 1. Thus, air and heat are exhausted from heat/air-exhausting slits (not shown) arranged at the upper portion of the image recording apparatus 1.
As a result of determining the arrangements of both the laser exposing unit 11 and the heat development unit 15, the mounting trays 5 and 6 are disposed in the intermediate portion of the image recording apparatus 1. Otherwise, in view of the user operability when the recording materials 3 are mounted on the mounting trays 5 and 6, the mounting trays 5 and 6 are disposed in the intermediate portion.
The transporting mechanism 17 has deriving means 31, first transporting means 32, second transporting means 34a, 34b, 34c, and third transporting means 38a, 38b. The deriving means 31 draws out the recording materials 3 from the respective mounting trays 5 and 6 one sheet by one sheet. The first transporting means 32 transports the recording materials 3 drawn out from the mounting trays 5 and 6 to the laser exposing unit 11. The second transporting means 34a, 34b, and 34c transport the recording materials 3 which have been carried out the exposure process from the laser exposing unit 11 to the heat development unit 15. The third transporting means 38a and 38b eject the recording materials 3 to which the developing process have been completed onto an ejection tray 36.
As mentioned above, the laser exposing unit 11 and the heat development unit 15 are separated from each other along upper/lower directions while sandwiching the mounting trays 5 and 6 arranged in the intermediate layout portion of the conventional image recording apparatus 1. Therefore, the transporting mechanism 17 employs such a transporting system that transports the recording material 3 to the laser exposing unit 11 at the lower portion in order to expose the laser on the recording material 3, and then transports to the heat development unit 15 at the upper portion. Therefore, the length of the transport path for the recording material 3 is made longer, so that the processing time is prolonged.